1 #!/usr/bin/env python

     2 

     3 """

     4     Python clone of the pngtile binary.

     5 """

     6 

     7 import optparse

     8 

     9 import pypngtile as pt

    10 

    11 # CLI options

    12 options = None

    13 

    14 def log_debug (fmt, *args) :

    15     if options.debug or options.verbose :

    16         print fmt % args

    17 

    18 def log_info (fmt, *args) :

    19     if not options.quiet :

    20         print fmt % args

    21 

    22 def log_warn (fmt, *args) :

    23     print fmt % args

    24 

    25 

    26 def parse_hex (hex) :

    27     """

    28         Parse a 0xHH.. style string as a raw bytestring

    29     """

    30 

    31     if not hex.startswith("0x") :

    32         raise ValueError(hex)

    33 

    34     return hex[2:].decode("hex")

    35 

    36 def parse_args (args) :

    37     """

    38         Parse given argv[1:]

    39     """

    40 

    41     global options

    42 

    43     parser = optparse.OptionParser(

    44             usage   = "Usage: %prog [options] <image file> [...]",

    45     )

    46 

    47     # build opts list

    48     parser.add_option('-q', "--quiet",          help="Supress informational output",                        action='store_true')

    49     parser.add_option('-v', "--verbose",        help="Display more output",                                 action='store_true')

    50     parser.add_option('-D', "--debug",          help="Equivalent to -v",                                    action='store_true')

    51     parser.add_option('-U', "--force-update",   help="Unconditionally update the image caches",             action='store_true')

    52     parser.add_option('-N', "--no-update",      help="Do not update the image caches, even if unusable",    action='store_true')

    53     parser.add_option('-B', "--background",     help="Background pattern for sparse cache file",            metavar="0xHH..")

    54 

    55     # parse

    56     options, args = parser.parse_args(args=args)

    57 

    58     # decode

    59     if options.background :

    60         try :

    61             options.background = parse_hex(options.background)

    62 

    63         except ValueError :

    64             raise ValueError("Invalid value for --background: %s" % options.background)

    65 

    66     return args

    67 

    68 

    69 def process_image (image) :

    70     """

    71         Process given image

    72     """

    73 

    74     # check cache status

    75     status = image.status()

    76 

    77     # update if stale?

    78     if status != pt.CACHE_FRESH or options.force_update :

    79         # decode status

    80         if status == pt.CACHE_NONE :

    81             log_info("\tImage cache is missing")

    82         

    83         elif status == pt.CACHE_STALE :

    84             log_info("\tImage cache is stale")

    85 

    86         elif status == pt.CACHE_INCOMPAT :

    87             log_info("\tImage cache is incompatible")

    88 

    89         elif status == pt.CACHE_FRESH :

    90             log_info("\tImage cache is fresh")

    91 

    92         else :

    93             log_warn("\tImage cache status unknown: %d", status)

    94 

    95         

    96         # update unless supressed

    97         if not options.no_update :

    98             log_info("\tUpdating image cache...")

    99             

   100             # update with optional background color

   101             image.update(background_color=options.background)

   102 

   103             log_debug("\tUpdated image cache")

   104 

   105         else :

   106             # warn

   107             log_warn("\tSupressing cache update even though it is needed")

   108 

   109     else: 

   110         log_debug("\tImage cache is fresh")

   111 

   112     # show info

   113     info = image.info()

   114 

   115     log_info("\tImage dimensions: %d x %d (%d bpp)", info['img_width'], info['img_height'], info['img_bpp'])

   116     log_info("\tImage mtime=%d, bytes=%d", info['image_mtime'], info['image_bytes'])

   117     log_info("\tCache mtime=%d, bytes=%d, blocks=%d (%d bytes), version=%d", 

   118             info['cache_mtime'], info['cache_bytes'], info['cache_blocks'], info['cache_blocks'] * 512, info['cache_version']

   119     )

   120 

   121 

   122 def process_images (image_paths) :

   123     """

   124         Open up each image_path and process using process_image

   125     """

   126 

   127     for image_path in image_paths :

   128         log_debug("Loading image: %s", image_path)

   129 

   130         # open up

   131         image = pt.Image(image_path, pt.OPEN_UPDATE)

   132 

   133         log_info("Opened image: %s", image_path);

   134 

   135         # process

   136         process_image(image)

   137 

   138 

   139 def main (args) :

   140     """

   141         Operate on given argv[1:]

   142     """

   143 

   144     # parse opts/args

   145     args = parse_args(args)

   146     

   147     # handle each image

   148     process_images(args)

   149 

   150 

   151 if __name__ == '__main__' :

   152     from sys import argv

   153 

   154     main(argv[1:])

   155